This invention relates to charge pump circuits, and more particularly, to charge pump circuits having current matching, non-startup prevention, and programmable current steering capabilities.
Charge pumps are used in circuits such as phase-locked loops in clock and data recovery circuits. Accurate charge pump behavior is important to ensure optimum performance of the phase-locked loop.
Charge sharing effects and current mismatch effects adversely affect charge pump performance. These effects reduce the accuracy of conventional charge pumps and the circuits in which these conventional charge pumps operate.